Apparatus for loading frangible containers

ABSTRACT

A machine is disclosed for loading frangible containers, such as relatively tall glass bottles of the thin walled-non-returnablevariety, into upwardly open packing cases. The bottles are conveyed in discrete side-by-side lanes into a grid structure where they are isolated by conventional brake means associated with each lane. A frame arranged over the grid structure carries a vertically reciprocable carriage having a plurality of individual container gripping units for holding a group of containers while a bottom portion of the grid is opened. Means is provided for retracting the frame and the grid structure slightly, away from those bottles being held by the brake means so that the carriage can be lowered and the bottles passed downwardly through the open grid structure into the case. Each gripper unit comprises a hollow tubular stem portion supported from the carriage, and a lower housing portion which contains a generally U-shaped spring member having depending leg portions with laterally opposed jaws at their respective ends for engaging the neck portion of a container. Each unit also includes a rod slidably mounted in the tubular stem, and connected to the apex of each spring member so that a vertically reciprocable plate in the carriage, to which the upper ends of these rods are connected, can be moved vertically to open and close the jaws on a container.

United States Patent [4 1 Mar. 14, 1972 Raudat et a1.

[54] APPARATUS FOR LOADING FRANGIBLE CONTAINERS [72] Inventors: John L.Raudat, North Madison; Lloyd D.

Johnson, Portland, both of Conn.

[73] Assignee: Ernhart Corporation, Bloomfield, Conn.

[22] Filed: Aug. 11, 1970 [21] Appl. No.: 62,961

[52] 0.5. CI... ..53/6l, 53/166, 53/247 [51] Int. Cl ..B65b 57/10 [58]Field of Search ..53/6l 166, 247

[56] I References Cited UNITED STATES PATENTS 2,730,279 1/1956 Enock..53/166 2,760,316 8/1956 Okulitch et a1. ..53/61 PrimaryExaminer-Travis S. McGehee Attomey-McCormick, Paulding & Huber ABSTRACTA machine is disclosed for loading frangible containers, such 1 asrelatively tall glass bottles of the thin walled-non-retumable-variety,into upwardly open packing cases. The bottles are conveyed in discreteside-by-side lanes into a grid structure where they are isolated byconventional brake means associated with each lane. A frame arrangedover the grid structure carries a vertically reciprocable carriagehaving a plurality of individual container gripping units [For holding agroup of containers while a bottom portion of the grid is opened. Meansis provided for retracting the frame and the grid structure slightly,away from those bottles being held by the brake means so that thecarriage can be lowered and the bottles passed downwardly through theopen gn'd structure into the case. Each gripper unit comprises a hollowtubular stem portion supported from the carriage, and a lower housingportion which contains a generally U-shaped spring member havingdepending leg portions with laterally opposed jaws at their respectiveends for engaging the neck portion of a container. Each unit alsoincludes a rod slidably mounted in the tubular stem, and connected tothe apex of each spring member so that a vertically reciprocable platein the carriage, to which the upper ends of these rods are connected,can be moved vet-- tically to open and close the jaws on a container.

8 DQ1112 Fi g Egg/1111111 APPARATUS FOR LOADING FRANGIBLE CONTAINERSBACKGROUND OF INVENTION This invention relates to machines for loadingfrangible containers into upwardly open packing cases such as thosereferred to in the trade as drop packers, wherein groups of containersare adapted to be dropped through a sequentially open grid structure.The conventional grid structure includes funnel means for lessening theimpact between the container and the case, but such funnel means is notrequired in the machine to be described herein.

In drop packing tall frangible containers, such as quart and half-gallonbottles or larger, especially where these bottles are of the thinwaIIed-non-returnable-type, it has been found that the conventionalfunnels used to lessen this impact do not adequately serve theirintended purpose. A primary aim of the present invention, then, is toprovide an attachment for a conventional drop packer of the foregoingtype, which attachment will permit the drop packer to handle frangiblecontainers without encountering the objectionable impact between thecontainers and the case.

In carrying out the foregoing aim of the present invention, a verticallyreciprocable carriage is provided over the conventional grid structure,and individual container gripping units are provided in this carriagefor lowering the containers at a controlled rate through the open gridstructure into the packing case.

Carriages for handling bottles have been proposed heretofore, forexample in US. Pat. No. 2,712,405 issued to Rockcastle in I955 a caseloading machine is shown having bottle gripping tongs mounted on avertically movable carriage. However, this patent does not show orsuggest the means for handling a group of containers fed to a gridstructure in a plurality of lanes, which containers are then lowereddownwardly without having to be transferred horizontally from onediscrete station to another prior to being lowered into a packing case.

As mentioned above, Rockcastle utilizes gripping units of the tong type,but other gripping units have been used in machines of this generaltype. Examples of other prior art patents showing gripping units orheads designed to handle glass bottles are shown in US. Pat. No.2,863,579 issued to 'Meyer in 1958, and U.S. Pat. No. 2,918,325 issuedto Gibson in I959. It will be apparent from an inspection of thegripping units shown in these patents that each such unit requires thatthe carriage move downwardly over the bottles to be gripped, and thatthe grippers be sequentially actuated after lowering of the carriage.The carriage must then be subsequently raised so that the articles canbe transferred to a succeeding station in the machine.

In the present disclosure, the carriage need not be moved downwardly inorder to grip the containers, and the containers, as a result, are freeto move in lanes between the depending leg portions ofa U-shaped springin the gripping units disclosed herein. These leg portions are closedaround the necks of the bottles without any necessity for lowering thecarriage in order to so grip the bottles. The carriage is subsequentlylowered to drop the gripped bottles through a sliding grid structureinto the packing case without having to first move through asubstantially horizontal displacement in a manner characteristic of theprior art machines discussed hereinabove.

SUMMARY OF INVENTION Means is provided for conveying frangiblecontainers into a grid structure of the type used in a conventional droppacker, that is into a grid structure having a sliding bottom portionmovable between open and closed positions. A frame over the gridstructure supports a vertically movable carriage having a plurality ofgripping units which can be closed over the tops of the containers togrip them in order to permit opening of the grid. The carriage thenlowers the gripping units and containers to load the latter into astationary packing case. The

gripping units then release the containers, and the carriage returns toits raised position prior to initiating a second cycle of operation.Each gripping unit comprises a housing having laterally spaced loweropenings through which spaced spring fingers depend for grippingopposite sides of the upper portion of a container. A verticallyreciprocable rod in each unit is adapted to move these fingers towardand away from one another so that jaws at the lower ends of the fingersgrip the containers, preferably just beneath an annular bead formed oneach container.

BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is an elevational view of thedownstream end of an apparatus incorporating the present invention,showing two side-by-side containers in two lanes just prior to actuationof the two gripping units located immediately thereabove.

FIG. 2 is a side elevational view of the apparatus shown in FIG. 11,with the lane defining grid structure containing three containers ineach of the two side-by-side lanes, and with brake means for holdingback containers on an infeed conveyor being shown schematically.

FIG. 2A is a sectional view taken on line 2A--2A of FIG. 2.

FIG. 3 is a vertical sectional view taken on line 3-3 of FIG. I throughone of the six gripping units shown in FIGS. I and 2, with portionsthereof being omitted to better show the configuration of the housing.

FIG. 4 is a vertical sectional view through the same gn'pping unit, buttaken on the line 4-4 of FIG. 3, and showing in schematic fashion themechanism for operating this unit.

FIG. 5 is a side view of the FIG. 4 gripping unit but taken at aslightly later instant of time to show the spring leg portions holding acontainer against the adjustable stop provided in a lower portion of thehousing.

FIG. 6 is a schematic view of the carriage and its actuator togetherwith the means for operating the gripping units, showing thesecomponents in their FIG. 1 position, and showing a packing case inposition for loading.

FIG. 7 is a view similar to FIG. 6 but shows the containers gripped bythe gripping units and the grid structure in its open configuration.

FIG. 8 is a view similar to FIGS. 6 and 7 but taken at a slightly laterinstant of time, the carriage being shown lowered and the gripping unitsafter releasing the containers into the packing case.

FIG. 9 is an electrical schematic diagram showing a control means foroperating the apparatus of FIGS. 1 thru 8 inclusively.

DETAILED DESCRIPTION Turning now to the drawings in greater detail, FIG.2 shows a plurality of frangible containers in the form of large thinwalled glass bottles, B, B being conveyed from left to right on aninfeed conveyor 10 of the conventional construction and having a fixeddead plate 112 located at the downstream end thereof. A conventionalline brake 14 is arranged above the dead plate so as to periodicallyinterrupt the flow of containers on the infeed conveyor and to causethem to stop in the position shown whenever a lane defining gridstructure 16 is filled with a predetermined number, or group of thesecontainers. As shown three containers are provided in each row in thegrid structure illustrated in the drawings, and two such lanes areprovided in side-by-side relationship in the grid structure shown. Thesetwo lanes are defined by a center wall 18 and left and right hand lanedefining walls 20 and 22.

The grid structure 16 further includes a bottom portion, indicatedgenerally at 24-, which comprises a horizontally slidable grid portionwhich is movable between a first position (not shown) wherein the gridstructure is downwardly open, and a second position, best shown in FIG.1, wherein longitudinally extending tails 26 and 28 are located incentered relationship beneath the containers B,B in each of theSide-by-side lanes, preventing them from dropping downwardly through thegrid structure. A fluid motor 30 is provided with a fixed portion and amovable portion 32 connected by a bracket 34 to the sliding grid portion24 so as to shift the grid portion 24 between its first and its secondposition.

It will be apparent that the portion of the mechanism just described canbe used for drop packing articles into an upwardly open packing case atleast where the articles are not so frangible as to be likely to breakwhen so packed. The packing case is located immediately below the gridstructure, and the articles fed into the grid structure on the tails 26and 28 until lane detector switches LS-l sense that the grid structureis fully loaded with containers at which time the cylinder 30 wouldshift the grid from the position shown to an open position whereupon thebottles would be allowed to drop downwardly into the packing cases (notshown). It has been found that with frangible containers such as 1 quartand w-gallon non-deposit-non-returnable bottles that these containersare not adapted to be so packed. Even if a funnel device is adapted foruse beneath the grid structure it has been found that such frangiblecontainers are apt to become damaged when allowed to freefall in adistance in excess of their own height. In order to be able to handlecontainers of this type in a machine designed to package containerswhich can be drop packed in the manner described above, attachmentmeans, to be described, is provided above the grid structure inconjunction with a control mechanism for operating the components ofthis attachment means, and these elements will now be described indetail.

As best shown in FIG. 2 the grid structure 16 is mounted onlongitudinally extending horizontal ways 38, 38 which permit the gridstructure to be retracted slightly, or moved in a downstream direction,so that bottles in the grid structure 16 are clear of the bottles beingheld by the line brake I4. Thus, the grid structure comprises aself-contained unit slidably mounted in a fixed frame 36, which framedefines fixed ways or rails 38, 38. A grid retract cylinder 40 isprovided for moving the entire grid structure no more than a fraction ofan inch in order to provide the above mentioned clearance between thelast bottle in the grid structure and the bottle being clamped by theline brake 14. An upwardly extending bracket 39is connected to the frame36 and supports the actuator cylinder 40 for this purpose.

A generally U-shaped frame 42 extends upwardly from the grid structure16, as shown in FIGS. 1 and 2, and this frame slidably supports avertically reciprocable carriage 44. Laterally opposed end portions ofthe carriage 44 are slidably supported in the depending leg portions ofthe frame 42 on vertically extending guide rods 43, 43, preferably bythe slide blocks 45, 45. A center portion of the carriage 44 isconnected to the movable portion 46 of a conventional fluid motor or aircylinder 48. As so constructed the carriage 44 can be raised to theposition shown in FIG. 1, and indicated schematically in FIGS. 6, orlowered to the position best indicated schematically in FIG. 8. As bestshown in FIGS. 1 and 2 the frame 42 supports the carriage 44 by a systemof chains and sprockets 50 and 52 which are connected to the carriageand to counter weights in the depending leg portions of the frame forbalancing the weight of the frame. The air cylinder 48 is adapted toraise the carriage 44 from the FIG. 8 to the FIG. 6 position under thecontrol of a valve (not shown) which is in turn controlled by solenoidE. The carriage is lowered by gravity when solenoid E is deenergized byventing the air cylinder to atmosphere. A pair of snubbers 54, 54 areprovided in the frame of the machine and have depending plugs 53, 53which are adapted to be engaged by pins 55, 55 provided for this purposeon the carriage in order to provide a cushioned stop for the carriagewhen it is raised from the FIG. 8 position to the FIG. 6 position. Avertically oriented cam 56 is provided on the carriage for tripping alimit switch LS-3 as the carriage reaches'its raised position, and foralso closing this switch when the carriage reaches its lowered position.As shown in FIG. 2 a second limit switch LS-4 is also provided toindicate when the carriage has reached its raised position. The functionof the limit switches LS-3 and LS-4 will be discussed in greater detailwith reference to FIG. 9 in discussing the operation of the apparatus.Adjusting knobs S7, 57 are provided for these switches to permit settingup the machine to accommodate bottles of various size.

As best shown in FIG. 1, the carriage 44 includes a horizontallyextending plate 60 which is adapted to be moved with respect to thecarriage in response to actuation of a plurality of relatively shortstroke air cylinders 62, 62. Actuation of these "pancake cylinders 62,62 causes corresponding movement of the rods 64, connected to the plate60 as shown in FIG. 4. Each rod 64 is thus adapted to be reciprocablymoved either upwardly or downwardly in a tubular stem portion 66 of eachof the gripping units associated with each of the containers B,B.

Turning now to a more detailed description of each of these grippingunits, FIG. 4 shows in vertical cross section the configuration of onesuch gripping unit. The outer tubular stern portion 66 comprising theupper portion of the gripping unit is connected to the carriage 44 andthe inner'actuating rod 64 slidably received in the tubular stem portion66 is connected to the horizontally extending plate 60 associated withthe four cylinders 62, 62. Each gripping unit includes a lower housingportion 68 which is hollow and into the hollow portion of which thelower end of the actuating rod 64 extends. A generally inverted U-shapedspring member 70 is connected at its apex portion to the lower end ofthe actuating rod 64, preferably by means of a generally cylindricalmounting member 72 and a contoured spacer 74 both of these being clampedtogether by means of a locknut 76 so as to support the spring memberwith its leg portions in depending relationship. The leg portions of thespring member 70 extend downwardly through openings provided for thispurpose in the lower wall of the housing 68 and are adapted to be cammedinwardly toward one another in response to upward movement of the rod64. The housing itself comprises a generally frustoconical upper portionand a generally annular lower portion, which portions cooperate todefine a suitablehollow receptacle for receiving the connection betweenthe actuator rod 64 and the spring member 70. The lower end portion ofeach of the leg portions of the spring member carries a suitablecontainer engaging jaw 78 and each of the leg portions shown has anintermediate portion for engaging the outer radial edges of thedownwardly open holes in the lower wall of the housing 68. In theembodiment shown in FIG. 4 a small cam 80 is provided at theintermediate portion of each leg of the spring member 70 so as toachieve a predetermined path of movement of these jaws when theactuating rod 64 is raised upwardly in response to energizing of thecylinders 62, 62. Depending upon the configuration of the containersbeing gripped by the unit these cam members may or may not be required.The lower wall of the housing 68 further includes an adjustable stopmember 82 against which the jaws 78, 78 can act so as to firmly grip acontainer at three discrete points prior to lowering of the containerthrough the grid structure into a packing case positioned therebelow.This stop member 82 comprises a resilient lower portion which may beformed of rubber or the like, as indicated generally at 84, and has anupstanding threaded portion which is adapted to be threadably receivedin a socket provided for this purpose in the lower wall 69 of thehousing. A locknut is provided, as indicated generally at 86, foranchoring this stop 82 in a predetemiined position for handlingcontainers of a predetermined configuration. It will also be apparentthat the jaws 78, 78 may be chosen for gripping containers ofpredetermined configura tion, and it is a feature of the presentinvention that the housing is fabricated in two parts, the lower portionor part being removable so as to permit removal and replacement of thespring member 70 and of the lower wall defining portion itself so as toaccommodate containers of various sizes in a machine of the typedescribed herein.

FIG. 4 shows a bottle prior to being gripped by the gripping unit, andFIG. 5 shows the unit after the actuating rod has been raised and theU-shaped spring member 79 compressed as a result of being pulledupwardly within the fixed housing, thereby urging the leg portionstoward one another and the jaws into engagement with the neck of thebottle just below the annular head on the container so as to pull thebottle off the grid rails 26 and 28 a very slight distance upwardlyagainst the fixed stop ill, and more particularly against the lowerrubber portion 84 thereof, so as to support the container prior toshifting of the grid from its closed position, shown in FIGS. l and 6,to its open position, best shown in FIG. 7. As indicated schematicallyin FIG. 7 the air cylinder 30 is adapted to shift the grid so as to openthe grid prior to lowering of the carriage 44 and lowering of thecontainers into the awaiting packing case C located on a conveyor or thelike indicated generally at 96.

The operation of the above described apparatus can best be summarizedwith reference to FIG. 9 wherein a control diagram is shown capable ofoperating a machine incorporating the features described above. Limitswitches LS1l are provided adjacent the downstream end of each of thelanes in the grid structure 16 and these switches are closed when eachof these lanes has been filled with a predetermined number of containersor bottles, as shown in FIGS. I and 2. Closing of this limit switchLS-ll energizes a relay TDR-lI causing its associated contacts,indicated generally at 92, to time close with the result that theminiature pancake cylinders 62, 62 are energized through solenoid Bclosing the spring members 70, 70 on the containers and raising them upoff the sliding grid structure in the manner described hereinabove withreference to FIGS. 4 and 5. At substantially the same time, the retractcylinder d6 associated with moving the grid slightly so as to allow aclearance to be created between the bottle held by the line brake l4 andthe last bottle to enter the grid structure, The line brake 114 willhave been energized through solenoid A immediately upon energizing relayTDRll as can be seen from line 2 of the schematic diagram. A secondrelay TDR-Z will be energized simultaneously with solenoids B and Cassociated with closing the grippers and retracting the grid for theabove-mentioned clearance. Relay TDR-Z has contacts, indicated generallyat 94 in FIG. 9, which will then time close so as to energize solenoid Dand shift the grid laterally from the FIG. 6 position to the FIG. 7position. A limit switch LS-2 is actuated when the grid 24 has shiftedto the FIG. 7 position indicating that the grid structure is open andthat the containers can be lowered into the packing case C on the conveyor 90. Thus as shown in FIG. 9 limit switch LS-2 deenergizes solenoidE associated with a valve (not shown) venting the air cylinder 48allowing the carriage 44 to be lowered by gravity from its raisedposition shown in FIG. 1 to the FIG. 8 position. Limit switch LS-3 is inengagement with the cam 56 provided for this purpose on the carriage,but when the carriage reaches its lowered position limit switch LS-3will be allowed to close energizing relay CR-I thereby opening thenormally closed contacts indicated generally at 96 in FIG. 9deenergizing solenoid B and allowing the pancake cylinders 62, 62 toreturn to their normal position opening the grippers and releasing thebottles so as to allow them to fall a short distance into the packingcase C. At the same time, a second set of normally closed contacts,indicated generally at 98 in the same relay CR4, will open deenergizingsolenoid E allowing the valve mechanism associated with the air cylinder48 to supply air under pressure for raising the carriage 44 from theFIG. 8 position back to the FIG. 6 position. In the FIG. 6 position LS-4will be cammed closed when the carriage reaches the FIG. 6 positionenergizing relay CR-2. The normally closed contacts 106 of relay CR-2will open dropping out relay TDlR-ll. Contacts 92 of TDR-l reopencausing the grippers to reopen, the grid to move upstream slightly andrelay "FDR-2 to be deenergized. Contacts 94 of relay TDR-2 then reopento allow the grid to close in order to receive another charge or groupof containers, and as the grid shifts closed LS-2 will actuate TDR-3.When TDR-3 times out its contacts 1104 release the line brake l4recycling the apparatus for continuous operation.

We claim:

l. in a machine for packing frangible containers in a packing case andincluding means for conveying containers to a pick-up station and meansfor conveying cases to be packed to a loading station spaced below thepick-up station, the improvement comprising a lane defining gridstructure for receiving groups of the containers in a predeterminedpattern, said grid structure including a laterally shifting portionmova' ble between a first position wherein it defines a downwardly opengrid and a second position wherein the grid is adapted to slidablyreceive the containers, a frame above said grid structure, a verticallyreciprocable carriage slidably supported in said frame for movementbetween raised and lowered positions, a plurality of container grippingunits each of which has an upstanding tubular stem and a lower hollowhousing portion, a rod slidably received in each of said tubular stems,a generally U-shaped spring member carried at the lower end of each rod,each spring member having its apex located in said housing portion andits leg portions depending from the housing, said leg portions havingend portions which define container engaging jaws and intermediateportions for engaging the outer edges of downwardly open holes in thelower wall of said housing, means connecting the upper ends of saidtubular stems to said carriage, means on said carriage for moving saidrods between raised and lowered positions to close and open said jaws oncontainers located therebetween, and control means for timing movementof said carriage with said rod moving means and with said shifting gridto sequentially grip the containers at the pick-up station, open thegrid, lower the carriage so that the containers are lowered into apacking case at the loading station, release the containers from thejaws, and raise the carriage to its raised position in position forreceiving a subsequent container group.

2. In a machine of the type defined in claim ll wherein said containerseach have a neck portion characterized by an annular projection adjacentthe upper end thereof, said combination recited in claim ll beingfurther characterized by each of said U-shaped spring members comprisinga strip of resilient material having an apex portion and generally fiatleg portions, each of said jaws comprising a projecting inwardlyextending member adjacent the ends of said respective leg portions forengaging said container projection.

3. In a machine of the type defined in claim 2 further characterized byadjustable stop means on the lower wall of each of said housing portionsfor engaging the upper end of each container as it is gripped betweensaid jaws, said jaws moving inwardly and upwardly in response to upwardmovement of said rod moving means to support the container at threepoints as it is lowered into the packing case.

4. The combination defined in claim ll wherein said means on saidcarriage for so moving said rods comprises a plurality of fluid motorshaving first portions connected to a surface on said carriage, saidconnecting means comprising a plate spaced from said carriage surface,said fluid motors having second portions movable with respect to saidfirst portions and connected to said plate, said rods being connected attheir upper ends to said plate for movement in response to movement ofsaid second fluid motor portions.

5. The combination defined in claim ll further characterized by brakemeans for holding back the containers on said c'ontainer conveyingmeans, said control means including container detect switch means forgenerating a signal when a group of containers has moved into positionin said grid struc ture, and said control means including means forenergizing said brake means in response to said signal.

6. The combination defined in claim 5 further characterized by means formoving said frame and said grid structure clear of said containerconveying means and said brake means, said control means including meansfor actuating said grid and frame moving means at substantially the sametime during a machine cycle when the containers are gripped.

7. The combination defined in claim 2 wherein said jaws are spaced apartlaterally in each of said. gripping heads so that when said carriage israised containers can be fed between said carriage to be gravity biaseddownwardly, and counter weight means for preventing excessive inertialforces on said frame when said carriage reaches a predetermined stopposition, said control means including limit switch means responsive toarrival of said carriage at said lower stop position to lower said rodsand open said jaws to allow a slight free fall of said containers intothe packing case.

1. In a machine for packing frangible containers in a packing case andincluding means for conveying containers to a pick-up station and meansfor conveying cases to be packed to a loading station spaced below thepick-up station, the improvement comprising a lane defining gridstructure for receiving groups of the containers in a predeterminedpattern, said grid structure including a laterally shifting portionmovable between a first position wherein it defines a downwardly opengrid and a second position wherein the grid is adapted to slidablyreceive the containers, a frame above said grid structure, a verticallyreciprocable carriage slidably supported in said frame for movementbetween raised and lowered positions, a plurality of container grippingunits each of which has an upstanding tubular stem and a lower hollowhousing portion, a rod slidably received in each of said tubular stems,a generally CU-shaped spring member carried at the lower end of eachrod, each spring member having its apex located in said housing portionand its leg portions depending from the housing, said leg portionshaving end portions which define container engaging jaws andintermediate portions for engaging the outer edges of downwardly openholes in the lower wall of said housing, means connecting the upper endsof said tubular stems to said carriage, means on said carriage formoving said rods between raised and lowered positions to close and opensaid jaws on containers located therebetween, and control means fortiming movement of said carriage with said rod moving means and withsaid shifting grid to sequentially grip the containers at the pick-upstation, open the grid, lower the carriage so that the containers arelowered into a packing case at the loading station, release thecontainers from the jaws, and raise the carriage to its raised positionin position for receiving a subsequent container group.
 2. In a machineof the type defined in claim 1 wherein said containers each have a neckportion characterized by an annular projection adjacent the upper endthereof, said combination recited in claim 1 being further characterizedby each of said U-shaped spring members comprising a strip of resilientmaterial having an apex portion and generally flat leg portions, each ofsaid jaws comprising a projecting inwardly extending member adjacent theends of said respective leg portions for engaging said containerprojection.
 3. In a machine of the type defined in claim 2 furthercharacterized by adjustable stop means on the lower wall of each of saidhousing portions for engaging the upper end of each container as it isgripped between said jaws, said jaws moving inwardly and upwardly inresponse to upward movement of said rod moving means to support thecontainer at three points as it is lowered into the packing case.
 4. Thecombination defined in claim 1 wherein said means on said carriage forso moving said rods comprises a plurality of fluid motors having firstportions connected to a surface on said carriage, said connecting meanscomprising a plate spaced from said carriage surface, said fluid motorshaving second portions movable with respect to said first portions andconnected to said plate, said rods being connected at their upper endsto said plate for movement in response to movement of said second fluidmotor portions.
 5. The combination defined in claim 1 furthercharacterized by brake means for holding back the containers on saidcontainer conveying means, said control means including container detectswitch means for generating a signal when a group of containers hasmoved into position in said grid structure, and said control meansincluding means for energizing said brake means in response to saidsignal.
 6. The combination defined in claim 5 further characterized bymeans for moving said frame and said grid structure clear of saidcontainer conveying means and said brake means, said control meansincluding means for actuating said grid and frame moving means atsubstantially the same time during a machine cycle when the containersare gripped.
 7. The combination defined in claim 2 wherein said jaws arespaced apart laterally in each of said gripping heads so that when saidcarriage is raised containers can be fed between each of said jawsduring the formation of said subsequent container group, said carriageremaining in said raised position when said rods are raised to closesaid jaws on said containers.
 8. The combination defined in claim 7further characterized by means for snubbing movement of said carriage asit reaches its raised position, said means for moving said carriagecomprising a single action fluid cylinder which is energized by saidcontrol means to raise the carriage and de-energize to allow saidcarriage to be gravity biased downwardly, and counter weight means forpreventing excessive inertial forces on said frame when said carriaGereaches a predetermined stop position, said control means includinglimit switch means responsive to arrival of said carriage at said lowerstop position to lower said rods and open said jaws to allow a slightfree fall of said containers into the packing case.